Collections of digital media content, including still images, animated graphics and full-motion videos, can be presented as a collage in which multiple sources of content are displayed simultaneously in individual cells of the collage, such as shown in the example collage of FIG. 1 (cells 102, 104, and 106). In such a collage, the content may need to be adjusted accommodate the size and shape of each cell. For example, the content may be stretched or compressed to fit into the collage cell, although such techniques can cause visual distortions of the content. To avoid such distortions, the original aspect ratio of the content can be maintained by proportionally resizing the content to fit within the collage cell (e.g., by changing the zoom or magnification level). When resizing causes the content to be smaller than the collage cell, so-called letter or pillar boxing techniques can be used to fill the portions of the cell not containing the content with a solid or patterned background (e.g., black bars). However, depending on the size of the cell, resizing the content at its original aspect ratio to fit within the cell may cause the content to become very small and thus difficult to view, or may cause portions of the content to be cropped out of view. Therefore, there is a need for improved techniques for placing content within a collage cell.